Where can you set the sampling rates for head-based sampling?

With head-based sampling, you can set rates:

• in the tracing library (env var such as DDTRACESAMPLERATE or code API) before spans are sent, and

• in the Datadog Agent using sampling rules.

Both layers apply independently, so configuration is available at either or both levels.

A. Library-only ignores Agent-side rules that can override or refine sampling.

B. Agent-only overlooks library variables that perform initial sampling.

D. Datadog explicitly supports head-based sampling rate configuration.

4. Datadog Docs – Configure Sampling, “Head-based sampling configuration,” paragraphs 1-3 (https://docs.datadoghq.com/tracing/configuresampling/?tab=agent#head-based-sampling-configuration)